An aircraft may use an onboard weather radar system to detect adverse weather conditions, which may enable the flight crew to make changes to the flight plan as necessary to avoid potentially hazardous weather. An aircraft in flight may also receive weather information from ground stations. Up-to-date weather information may assist the flight crew in evaluating whether or how to modify a flight plan to avoid hazards for the flight. Airborne weather radar detects reflectivity of weather associated with precipitation. Reflectivity of a radar signal is an electrical quantity related to the percentage of power (normalized for range) returned from the weather being illuminated by the radar transmission. Reflectivity is generally related to rate of precipitation.